Modern medical imaging assemblies have increased in complexity and capabilities. These increases often result in an increase in power requirements and associated wear on such assemblies. Such is the case with x-ray tube assemblies. Increases in power requirements of the imaging assembly can result in increases in the required rotational speed of the x-ray target assembly in order to prevent overheating and damage thereto. These increased rotational speeds may result in high hub stresses that exceed present design criteria. The hub is the center portion of a target assembly in communication with the drive shaft.
In addition to the additional stresses associated with the increase in power requirements, the target assembly itself will suffer an increase in wear and thermal damage. These increases stressors are well known to result in damage to the impact regions of the target element. In addition, the thermal energy may translate through the target assembly to enter the hub portion. The increase in thermal energy in combination with the increased stresses due to increased rotational speeds may result in undesirable wear and damage to the hub element.
In any design for an x-ray target assembly it is likely that the target element or portions thereof will suffer damaged during prolonged usage. This is simply a preordained result of the target element being impacted by an electron beam to facilitate the generating of x-rays. Yet when wear or damage becomes too great, existing designs require complete replacement. Disassembly and repair is not contemplated by existing designs and may be impractical based on design configurations and associated costs. Since such wear and damage may only be minimized, a design that introduced the potential for worn or damaged portions of the target element to be replaced would be beneficial. In addition, where repair is still not cost effective, a design that allowed reuse of at least a portion of the target assembly would provide desirable cost benefits.
It would, therefore, be highly desirable to have an x-ray tube target assembly that allows for simplified replacement of worn or damaged portions of the target element. It would also be highly beneficial to have an x-ray tube target assembly that was capable of withstanding the high rotational speeds and increased thermal requirements of modern anode performance.